[nyaligatoraron]

Are there any alternatives to a styrofoam background that looks as good or even better?
or possibly that does not include concrete?

 

[chmey]

This might be an alternative for you.

http://www.designsbynature.net/

 

[Cromak]

The design by nature is some good stuff, i have one that i was using in my 55 prior to painting my background black for a change of pace.

 

[The Novice]

If you're really gung-ho, you can form a back from plexiglass, and cure it. Check boat dealers for repair kits. (I'm old-fashioned, I just use the dull side of crinkled aluminum foil and tape.)